The goal of this project is to explore the therapeutic potential and biological effects of autologous plasma perfused over protein A in patients with breast cancer. Patients with recurrent measurable breast cancer and good performance status are treated with previously stored autologous plasma perfused over protein A immobilized on charcoal collodion. The dose of protein A and the quantities of plasma that is perfused are escalated in a stepwise fashion depending on the patient's tolerance. The patients are closely observed for evidence of objective tumor regression, inflammatory changes that may occur around the lesions, toxicity, and biological response modifying effects. Four patients have entered the trial to date and it is anticipated that 15 patients will be studied. Some patients have experienced pain around tumors following plasma therapy, but to date there have been no objective tumor regressions or toxicity. Animal studies performed by direct injections of protein A have not as yet shown any antitumor effects.